# Different magnetic field effects on the ϵ-τ Phase transformation between (mn,zn)-al and mn-al-c

Yoshifuru Mitsui, Ryota Kobayashi, Yudai Takanaga, Akio Takaki, Rie Y. Umetsu, Kohki Takahashi, Masaki Mizuguchi, Keiichi Koyama

Research output: Contribution to journalArticlepeer-review

2 Citations (Scopus)

## Abstract

In-magnetic-field annealing (IFA) effects on Zn-modified Mn-Al and Mn-Al-C were investigated at the annealing temperature of 573 K, which was around their $_Rftxt-{\mathrm {C}}$. Mn53Zn2Al45 showed the magnetic-field-induced acceleration of the phase transformation to $\text{L}1-{0}$ -phase ( $\tau$ -phase) and the suppression of that to nonferromagnetic equilibrium phase. For Mn55Al45C2, IFA effects were not clearly detected. These different magnetic field effects were discussed by the difference of the mechanism in stabilization of $\tau$ -phase. It is found by a thermal analysis that the modification of Zn stabilized $\tau$ -phase against $\epsilon$ -phase, realizing acceleration of transformation to $\tau$ -phase. The addition of carbon stabilized $\epsilon$ -phase against $\tau$ -phase. The ineffectiveness of in-field annealing for Mn-Al-C is due to the stabilization of $\epsilon$ -phase and the reduction of the Curie temperature. The combination of Zn modification and IFA is realized to synthesize high fraction of $\tau$ -phase for short annealing time and low annealing temperature.

Original language English 8443145 IEEE Transactions on Magnetics 55 2 https://doi.org/10.1109/TMAG.2018.2860559 Published - 2019 Feb

## Keywords

• High magnetic field
• Mn-al
• Permanent magnet

## ASJC Scopus subject areas

• Electronic, Optical and Magnetic Materials
• Electrical and Electronic Engineering